in dapper, when performing "apt-get update" i get an error message

in dapper, when performing "apt-get update" i get an error message. i have been getting this message, everytime that i attempt to update my package lists, since installing dapper about one month ago.

by using firefox, i was able to download and open the relevant "Packages.gz" file without a problem.

i'm not sure if this is a problem with the netork/server or an actual bug in Ubuntu, but there should certainly be a better error message in either case.

the error that the terminal spit out was:

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alex@alex-laptop:~$ sudo apt-get update
Get:1 http://security.ubuntu.com dapper-security Release.gpg [189B]
Get:2 http://us.archive.ubuntu.com dapper Release.gpg [189B]
Get:3 http://us.archive.ubuntu.com dapper-updates Release.gpg [189B]
Hit http://us.archive.ubuntu.com dapper Release
Hit http://security.ubuntu.com dapper-security Release
Hit http://us.archive.ubuntu.com dapper-updates Release
Hit http://security.ubuntu.com dapper-security/main Packages
Ign http://us.archive.ubuntu.com dapper/main Packages
Hit http://us.archive.ubuntu.com dapper/restricted Packages
Hit http://us.archive.ubuntu.com dapper/main Sources
Hit http://security.ubuntu.com dapper-security/restricted Packages
Hit http://security.ubuntu.com dapper-security/main Sources
Hit http://security.ubuntu.com dapper-security/restricted Sources
Hit http://us.archive.ubuntu.com dapper/restricted Sources
Ign http://us.archive.ubuntu.com dapper-updates/main Packages
Hit http://us.archive.ubuntu.com dapper-updates/restricted Packages
Hit http://us.archive.ubuntu.com dapper-updates/main Sources
Hit http://us.archive.ubuntu.com dapper-updates/restricted Sources
Get:4 http://us.archive.ubuntu.com dapper/main Packages [821kB]
99% [4 Packages gzip 0] [Waiting for headers]
gzip: stdin: not in gzip format
Err http://us.archive.ubuntu.com dapper/main Packages
  Sub-process gzip returned an error code (1)
Get:5 http://us.archive.ubuntu.com dapper-updates/main Packages [97.9kB]
99% [Working]
gzip: stdin: not in gzip format
Err http://us.archive.ubuntu.com dapper-updates/main Packages
  Sub-process gzip returned an error code (1)
Fetched 5B in 1s (5B/s)
Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/dapper/main/binary-i386/Packages.gz Sub-process gzip returned an error code (1)
Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/dapper-updates/main/binary-i386/Packages.gz Sub-process gzip returned an error code (1)
Reading package lists... Done
E: Some index files failed to download, they have been ignored, or old ones used instead.
alex@alex-laptop:~$
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